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Three years ago, this YouTube video of a talk by Dr.
Robert Lustig, a Professor of Pediatric Endocrinology at UC San Francisco, when
viral (to date, the video has 2.7 million downloads). His argument there, and subsequently in prestigious
journals like Nature, is that sugar is toxic.

I’m going to be honest, I haven’t invested the time to
adequately evaluate the claims made about the biology, endocrinology, and
metabology of sugar, but I suspect there is some truth to the argument that
some foods are metabolized differently than others – in other words, it is more
complicated than just “calories in, calories out” (although this adage is also
almost certainly true on some level).

What I do know is that the science of sugar is not nearly as
certain as Lustig purports, a fact mentioned
by Gary Taubes who is overall sympathetic to his claim (see also the citations
in second paragraph of Lustig’s Wikipedia page).

Lustig is an accomplished and well-published scientist. But, what bothers me is the all too common
stance of many folks in the medical and public health communities failing to
appreciate how little they know when they move to realms beyond their
particular academic expertise.

The viral YouTube talk included a beginning slide with the
words “Letting Science be the Guide” and Lustig personally began a speech in 2011 by
asserting that “Ultimately science should drive policy.” Yet, I find it a bit
ironic that neither of these talks seriously discusses the economic science behind the many sugar-recuing policies he
supports.

Economic study
after study
after study
after study
shows sugar policies (such as sweetened beverage taxes or bans on school
vending machines) will only have very small effects on intake and weight. When sodas are taxed (or banned), people can
substitute toward other caloric drinks such as fruit juice or alcohol.
Moreover, food taxes are regressive - meaning the burden is disproportionately
borne by the poor. It is also worth
pointing to the economic research
on farm policy and sugar production reveals a much more complicated situation
than many pundits presume, with the authors
showing that the “link between US sweetener consumption and farm policy is
weak.”

So the next time you hear someone pronounce
that the “government has to get off its ass” because of sugar consumption, I
suggest asking what economic science actually says about what will happen when
the government moves it’s preverbal backside.

Addendum: One of my
colleagues pointed out that the arguments used to claim sugar is addictive
(primarily that our body becomes accustomed to a level of intake and requires
more and more to achieve a given level of satisfaction) sounds remarkably like
the psychologist’s notion of the hedonic treadmill – a
phenomenon that is posited to hold for almost all aspects of life.